Zaymiey

🧪 Chemistry  ·  Aldehydes, Ketones and Carboxylic Acids  ·  NEET & JEE

What type of reaction occurs when acetaldehyde reacts with semicarbazide?

Answer: Condensation.

  • A Nucleophilic addition
  • B Electrophilic addition
  • C Free radical
  • D Condensation

Correct answer: D. Condensation

Explanation: Reaction with semicarbazide involves nucleophilic addition followed by loss of water (condensation).

Nucleophilic Addition to C=ONu:-CORR'CO-RR'Nu

Curved arrows show the nucleophile attacking the carbonyl carbon while the C=O pi electrons move onto oxygen, giving a tetrahedral alkoxide intermediate.

Concept context

Aldehydes, ketones, carboxylic acids, and their derivatives (esters, amides, acid chlorides). Key reactions include nucleophilic addition, Aldol condensation, Cannizzaro, and Claisen. Very heavily tested in JEE and NEET.

Read the full Aldehydes, Ketones and Carboxylic Acids notes →